Abstract
We examine the nonclassical property of a Schrödinger cat state, i.e., a superposition of two coherent states, when it is amplified by either a phase-sensitive or a phase-insensitive amplifier. In both cases the corresponding P representation remains nonpositive in some area of the complex plane, for any amplification factor. The contribution to the P function from these areas decreases exponentially with an amplification factor. With a phase-sensitive amplifier the onset of decay can be postponed to a larger amplification factor. Thus the nonclassical nature of the field can be preserved under a wide range of conditions, in spite of the noise introduced in the amplification process.
Original language | English |
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Pages (from-to) | 1027-1030 |
Number of pages | 4 |
Journal | Physical Review A |
Volume | 53 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1996 |